Method and apparatus for cooling dental impressions



8633i. 13, 1938. R BERKSON v ,987

METHOD AND APPARATUS FOR COOLING DENTAL IMPRESSIONS Fil ed June 21, '19s? INVENTOR RALPH BERK ON.

ArroR/ys I Patented Sept. 13, 1938 UNITED STATES PATENT OFFICE METHOD AND APPARATUS FOR COOLING DENTAL IIVIPRESSIONS 6 Claims.

This invention relates to a method of and apparatus for cooling dental impressions, although the teachings thereof may be employed with equal advantage for other purposes.

It contemplates more especially the provision of means for eifectively and instantly cooling dental impressions by resort to a highly compressed refrigerant so as to convert normally solid impression material heated to a semi-plastic state into a self-sustaining and form-retaining mass Without entailing any appreciable time.

Dental impressions have heretofore been cooled by resort to cold water, but this expedient is not entirely satisfactory due to the fact that appreciable time is required in permitting the impression to cool and the results are not always dependable or satisfactory. Then, too, the water available to a dentist is not always sufiiciently cold to produce the desired cooling effect. At least, the interior body of the impression material is not thoroughly cooled to render such completely self-sustaining and form-retaining in the preservation of the exact impression during the removal of the impression material from the mouth.

. One object of the present invention is to provide a new and novel method for cooling dental impressions and the like.

Another object is to provide a simple and improved apparatus for cooling impression material that has been heated to a semi-plastic state.

Still another object is to provide a novel method and simple and improved apparatus for effectively and thoroughly cooling impression material to render such self-sustaining and form-retaining without entailing any appreciable time interval.

A further object is to provide improved and simplified means for subjecting impression material to a refrigerant for the purpose of conducting heat therefrom.

A still further object is to provide a tray with an expansion tube for the purpose of receiving a highly compressed refrigerant to instantly cool impression material confined in the tray.

Still a further object is, to provide a novel single-hand control valve for injecting and controlling a highly compressed refrigerant supply'to an expansion tube having an impression material tray associated therewith.

Other objects and advantages will appear from the following description of an illustrative embodiment of the present invention.

In the drawing:

Figure 1 is a diagrammatic view of a dental impression tray having a refrigerant supply mechanism operatively connected bhclfewith. the refrigerant supply mechanism being shown in substantially reduced size to permit of a complete illustration.

Figure 2 is a fragmentary sectional view taken substantially along line II-II of Figure 1. 5 Figure 3 is a sectional view taken substantially along line IIIIII of Figure 1 with the stopper orifice shown in enlarged proportion.

Figure 4 is a sectional view taken substantially along line IV-IV of Figure 1 with the stopper 10 shown in enlarged proportion.

Figure 5 is a fragmentary sectional view in elevation of a valve control chamber similar to that shown in Figure 2 with an additional valve thereon for controlling the amount of liquid gas enter- 15 mg.

Figure 6 is a plan view of a modified form of refrigerant supply shown in Figure 1 wherein the refrigerant supply tank is incorporated as part of the valve handle. 20

The structure selected for illustration comprises a dental impression tray of any standard or approved construction and sized to meet the requirements of commercial practice. The dental impression tray I0 is preferably of ahighly thermal conductive material and provided with apertures l I therethrough so as to assist in the dissipation of heat and to lighten the burden of the tray l0 when applied to the teeth or in the mouth or wherever an impression is desired. The tray NJ is preferably provided in the concave surface thereof with the expansion tube l2 bent to conform with the general contour of'the tray Ill and to cover as much of the surface thereof as possible in order to efiect the cooling thereof with rapidity 35 and effectiveness.

As shown, the tray Illis provided with an extension l3 along a longitudinal median line thereof to facilitate the handling of the tray 10. In the present embodiment, the extremities l4 and I5 4-0 of the expansion tube 12 terminate in the region of the tray extension l3, the extremities l4 and 15 being provided with suitable enlarged orifices I6 and M, respectively, to enable the introduction and discharge of a refrigerant in a manner which 45 will appear more fully hereinafter. The refrigerant nozzle l6 consists of an enlarged flared tubular member formed integral or otherwise attached to the entrant extremity of the expansion tube l2 to receive a stopper l8 for sealed reception 50 therein, the stopper l8 being preferably of rubber or other resilient composition material. As shown, the stopper l8 has a slight concavity l9 axially therein to receive a pointed extremity of a hypodermic needle 20 that pierces the material of the stopper I8 to enable communication with the interior of the expansion tube [2.

The discharge orifice I! of the expansion tube I2 is similarly formed integral or otherwise attached thereto to receive a rubber stopper 2l in sealed engagement with the interior thereof, the stopper 2| being preferably of rubber or other resilient material and preferably has a central bore 22 therethrough to regulate the discharge of the expanded refrigerant therefrom. The size'of the stopper bore'22 may be varied within the requirements of commercial practice in order to produce the desired refrigerating effect by injecting'a highly compressed refrigerant such as Freon (F 12). Any other suitable refrigerant icanjbe substituted within the dictates of commercial practice, and good results can be procured "by merely spraying the refrigerant directly over the surface of the tray l0 rather than resort to the expansion tube l2.

The tray .lllis filled. with impression material in the customary .manner and thenplaced in the mouth to procure the desired impression as is now the practice. To .providefor a correctand perfect impression,.the normally solidimpression material must be slightly heated so as to convert such .into a semi-plastic state to conform with the shape of .thegumsection of the mouth to be fitted. After the impression has beenmade, the .highly. compressed refrigerant such .as Freon (F 12) is introduced intothe. expansion tube 12 so as to absorb the heat from the trayand the impression material to effect the immediate cooling thereof. By so doing, the impression material issoon converted to itsnormally solid self-sustaining and form-retaining state within two minutes :or less to preserve the impression for its intended purpose- In order to enable the dentist or practitioner to introduce the highly compressedrefrigerant without requiring an assistant,.the hypodermic needlelllhas-itshub 23 in sealed engagement with the discharge nozzle 24 seated to .a valve body. 25-by means of athreaded unionor coupling 26 (FigureZ). The valve body-25 is provided with a port 21. that communicates with the nozzle 24-andthe interior of the needle 20. .The port 21 communicates with a valve seat -28-within the tubular interior29 of the valve b0dy.2-5. A conical valve 30 confronts; the valve seat.28,.and has its .shank.3l reciprocally mounted in a threaded closure32, the closure 32 being in threaded engagement with the valve 25.and serves as a guide for the valve shank 3| that projects exteriorly therethrough.

To maintain the valve normally ,closed against its seat 28, a,coil spring 33 envelops the valve shank 3| between itsvalve head-.39 and the interior surface'of the valvebody closurei32..serv ing as guide for .the reciprocally-mounted valve shank 3!. The valve body 25 terminates in a tubular extension that has. a handle 35 of insulation material detachably or otherwise' .associated therewith, vthehandle 35 having a tubular interior for communication with theinterior of the-valvebody 25. Asshown, thethandle member 35 terminatesin a conical tubularextension 36 for enabling the connection of a flexible tube 31 thereto. V a r In orderto manipulate the valve 30,- a lever 38 is 'fltted'to the valve body extension 34 having afurcated'boss 39 provided thereon for that purpose. In order to pivotally sustain the handle lever'38, a pin '48 projects through'the furcated boss 39 and engages the lever 38 that has an arm 4| extending in the path of the valve shank 3| to effect an operative connection therebetween. It will be noted that the handle 35 may be grasped in one hand and the lever 38 manipulated with the fingers of the same hand to open the valve 30 against the urge of the spring 33 in order to introduce the highly compressed refrigerant in the expansion tube l2. To this end, the flexible tube 3'l is operatively connected to a refrigerant supply it ank '42 thathas aniadjustable valve 43 of standard construction provided there- I on. The tank valve 43 is provided with a discharge port 44 engaging the flexible tube 31 so 'as to complete thesupply line to the valve body 25 to "control the discharge of the refrigerant through the needle 20 in the manner described supra. Then, too, the highly compressed liquid gas can be sprayed directly on the tissues to freeze the skin and mucous membranes for surgicalpurposes. At the present time, only low pressure liquid ,gasessuch as-ethyl chloride have been used in surgery. vHighly compressed liquid gases sprayedinthe manner describedherein would be more efficient owing to their lower evaporating temperatures.

In the modified embodiment shown in Figure 5, thehandle member 35 isprovided with an enlarged tubular interior 34 that communicates with a hand valve- 45 to admit the highly compressed liquid gases to the interior chamber 34 of the handle35'. .Atubular extension 36' pro- -jects from the valve 45 forconnection to the flexible hose 3'! shown 'in Figures 1 and 2 leading from the supply tank 42 as illustrated in Figure 1. temporary storage compartment for a sufficient amount of liquid gas to solidify theimpressions or measured for any other .purposesfor which it is .used. The tubular handle35 is provided at its discharge end with .the valve body.25 (Figure 2) so that after the charge of compressed liquid gas is enclosed in .the handlecompartment 34', the handle valve .45,is closed and the finger manipulated valvehandlel38 (Figure 2) is compressed to affordthe .dischar'geof the highly .com-

Thetubularshandle .35 serves as a particular requirements depending upon the amount of liquid gasrequired and the purpose for which itLis intended.

..Should it .be -.desired,.the refrigerant supply tankAZ" may be connected directly to a. valve body-.25! .(Figure .6) that has a rigid discharge tube '46 operativelyconnected therewith to. receive a hypodermic needle 20" in communicating relation therewith. The valvebody 25" is provided with the valve; control lever .38" that is pivoted thereto .as.at .40." .so that its arm 4 I will be voperatively connected ..to the spring impelled valve stem ..3l.. .By so doing, the flexible tube 31 (Figure l.) :is .dispensdwith and a muchrnore compact and portable refrigerant supply unit is provided. It is .onlyinecessary to inject the hypodermic needlelfifinto the rubber. stopper. 18 (Figure 4) so as to introduce-the highly compressed refrigerant to the expansion tube I2.fixed to the impression tray l0 (Figure 1) unless it is desired to spray the refrigerant over the surface of the tray l0. 7

.With the arrangement of parts above described, it will be apparent that a very effective and improved method and apparatus for cooling dental impressions has been provided and such may be applied to other analogous uses depending upon the dictates of commercial practice. Various changes may be made in the embodiment of the invention herein specifically described without departing from or sacrificing any of the advantages or features of the invention, and nothing herein shall be construed as a limitation of the invention, its concept or structural embodiment as to the Whole or any part thereof except as defined in the appended claims.

1. An impression material device comprising a preformed tray of highly thermal conductive material, a refrigerant expansion tube applied to the surface of said tray, entrant control means at one end of said tube to tightly receive the discharge end of a refrigerant supply needle, a refrigerant discharge needle engaging said expansion tube entrant control means to communicate with the interior of said expansion tube, means for supplying a refrigerant through said needle, and. a valve for controlling the supply of a highly compressed refrigerant to said expansion tube.

2. In a cooling mechanism, the combination with a highly compressed refrigerant supply line, of a handle member in said supply line, a valve in said handle member, spring means for normally urging said valve to its closed position, a lever connected to said handle member to open said valve against the urge of said spring means with the finger of the hand grasping said handle member, a tubular needle connected at the discharge end of said handle member in front of said valve, a cooling tray, an expansion tube fixed to the surface of said cooling tray, and means in the entrant orifice of said expansion tube to receive said needle in sealed communication with the interior of said expansion tube.

3. In a cooling mechanism, the combination with a highly compressed refrigerant supply line, of a tubular handle member in said supply line, a valve associated with the discharge end of said handle member, a lever connected to said handle member to operate said valve with the finger of the hand grasping said handle member, another valve associated with the intake end of said tubular handle member to retain a predetermined supply of a refrigerant therein, and a tubular needle connected at the discharge end of said handle member in front of said valve.

4. In a cooling mechanism, the combination with a highly compressed refrigerant supply line, of a tubular handle member in said supply line, a valve associated with the discharge end of said handle member, spring means for normally urging said valve to its closed position, a lever connected to said handle member to operate said valve with the finger of the hand grasping said handle member, another valve associated with the intake end of said tubular handle member to retain a predetermined supply of a refrigerant therein, and a tubular needle connected to the discharge end of said handle member in front of said valve.

5. In a cooling mechanism, the combination with a highly compressed refrigerant supply line, of a tubular handle member in said supply line, a valve associated with the discharge end of said handle member, spring means for normally urging said valve to its closed position, a lever connected to said handle member to open said valve against the urge of said spring means with the finger of the hand grasping said handle member, another valve associated with the intake end of said tubular handle member to retain a predetermined supply of a refrigerant therein, a tubular needle connected at the discharge end of said handle member in front of said valve, a cooling tray, an expansion tube fixed to the surface of said cooling tray, and means in the entrant orifice of said expansion tube to receive said needle in sealed communication with the interior of said expansion tube.

6. An impression material device comprising a preformed tray of highly thermal conductive material, a refrigerant expansion tube applied to the surface of said tray, a solid rubber entrant stopper at one end of said tube to tightly receive the discharge end of a refrigerant supply needle, a refrigerant discharge needle engaging said expansion tube rubber entrant stopper to communicate with the interior of said expansion tube, means for supplying a refrigerant through said needle, and a valve for controlling the supply of a highly compressed refrigerant to said expansion tube.

RALPH BERKSON. 

